Learning Forum

[Mohamed_Wael_Badawy]

Dear sir,

I am simulating the motion of a droplet in a micro-channel where the droplet dynamics is highly dependent on the thin layer of fluid between the interface and the wall boundaries. 

I am trying to use VOF mesh adaption while i am using inflated mesh near the boundaries. However, I am always facing the problem of having a layer of non-adapted mesh between the inflated layers and the adapted zone. I have tried to separate the inflated mesh zone and retry the mesh adaption but i got the same results. I would like to know if there is a method that can successfully adapt the mesh according to the VOF in the vicinity of the inflated mesh zone.

[YasserSelima]

Do the adoption by coordinates using expression. Let's say you want to adopt the cells between x=0.05 m to x=0.1m ... use this expressionnIF(AND(Position.x < 0.1[m],Position.x>0.05[m]) , 1,0)n

[Mohamed_Wael_Badawy]

Thank you so much, I tried the coordinates as you suggested but it also leaves the same non adapted gapnn

[YasserSelima]

Try it without < .. like thisnIF(Position.y >0.05[m] , 1,0)nn

[Mohamed_Wael_Badawy]

Same result. Fluent intentionally leaves a layer of 1 element thick unadapted next to the inflated layers.n

[YasserSelima]

Not sure how to solve this. nYou have no option but going back to meshing if you want to solve this soon. The Ansys experts are off in the weekendsn

[Mohamed_Wael_Badawy]

Thanks for your help. What do you mean by going back to meshing?n

[YasserSelima]

How did you create your mesh in the first place. Go there and select smaller element size for this wall. And re-meshn

[Mohamed_Wael_Badawy]

I FINALLY managed to overcome this issue, I changed the minimum orthogonality ratio in the advanced mesh adaption to zero and it worked!n

[YasserSelima]

Thanks for sharing the solution!n